Cutting tools need to have wear resistance, welding resistance, and chipping resistance. Therefore, cutting tools in which coating layers formed on a surfaces of hard substrates such as WC-based cemented carbide or TiCN-based cermet are widely used.
In general, TiCN layers and TiAlN layers are widely used as such coating layers. Various coating layers are under development for the purpose of achieving higher wear resistance and enhanced chipping resistance.
For example, Patent Literature 1 discloses a (TiWSi)N coating layer, which has increased adhesion with a substrate. Patent Literature 2 discloses a (Ti, Al, W, Si, M (M is at least one selected from the group consisting of Nb, Mo, Ta, Hf, and Y))N coating layer, which has good oxidation resistance and chipping resistance.